Patent GB-1187050-A (GB)
Title: A Device Suitable for Coupling One End of a Rod to One End of a Shaft.
IPC: C30B13/28
Filed: 1967-12-07
Abstract: 1,187,050. Zone-melting. SIEMENS A.G. 7 Dec., 1967 [7 Dec., 1966], No. 55799/67. Heading B1S. [Also in Division F2] In an apparatus for melting a rod 2, 31 of crystalline, e.g. semiconductor, material, zone-by-zone, the rod is removably vertically clamped in bushes 3, 30 (respectively Figs. 1, 2), said bushes being in turn respectively connected to upper and lower shafts 11, 35 by devices each comprising First and Second Parts which respectively are fast with a corresponding shaft and bush and are provided with a First Means preventing radial whilst permitting and guiding thermally-produced axial relative movement between the Parts and a Second Means which whilst not preventing said relative radial movement prevents relative angular movement of the shaft and bush axes whenever the First arid Second Parts are axially engaged with each other. . The rod comprises a thick upper portion 2 and a thin lower portion 31 which is a seed crystal. Means, not shown, creates a molten zone in the rod and causes it to travel up the rod for polycrystalline/mono crystalline conversion, without using a molten material support crucible. The rod is clamped in each of the bushes 3, 30 by clamping screws 9, 37. The shafts 11, 35 are co-axial with the rod, are rotatable in the same or opposite directions by means not shown, and are axially displaceable towards and away from each other. It is intended that when the rod has been completely melted through, the rod portions 2, 31 shall rotate with the shafts 11, 35, respectively in the same or opposite directions. In Fig. 1 said First Part comprises a disc 5 integral or permanently fast with the shaft 11, or, as shown, removably secured thereto by a jaw 10. Said Second Part comprises a cup 4 radially and angularly adjustably connected to a plate 24 fast with the bush 3, the cup engaging a rounded stud 25 screwed into the plate 24 and being clamped to the latter by nuts 26 engaging screws fast with the cup 4 and accommodated in radial slots 15 in the plate 24. Said First Means comprises a pin 22 fast in the cup 4 (or the disc 5) and engaging a bore 12 in the disc 5 (or the cup 4). Said Second Means comprises a ball thrust bearing comprising balls 17 in a cage 18 and engaging a lid 7 fast with the cup 4 and a ring 6 angularly adjustably secured to the disc 5, there being provided screws 20, screwed into the disc 5 and bearing on the ring 6, and clamping screws 19. Said Second Means provides for frictional transmission of rotation between the cup 4 and the disc 5. On upward movement of the rod upper end due to expansion prior to the rod being completely melted through, the lid 7 is lifted from the balls 17, with the result that the shaft 11 is not coupled for rotation to the rod portion 2. When the rod is completely melted through, the rod portion 2 and the lid 7 fall, so that rotation of the shaft 11 can be transmitted to the rod portion 2. If the shaft 11 is not to be rotated, the ball thrust bearing may be replaced by three clawlike flange portions extending from the top of the cup 4, in place of the lid 7, and engaging. the disc 5. In Fig. 2, said First Part comprises a disc 28 integral or permanently fast with the shaft 35, or, as shown, removably secured thereto by screws 40. Said Second Part comprises a disc 39 welded or otherwise fastened to, or integral with, the bush 30, the disc 39 having an upturned rim 29 for retention in the bowl formed thereby of falling molten material. Said First Means comprises a pin 34 fast with the disc 39 (or the shaft 35 or the disc 28) and engaging a bore in the shaft 35 (or the disc 39 or the disc 28). Said Second Means comprises balls 32 seated in angularly adjusting screws 33 in the disc 28 and engaging the disc 39. Said Second Means provides for frictional transmission of rotation between the discs 28, 39.